Gasoline tank cap structure

ABSTRACT

A gasoline tank cap structure includes a base, a cap and a cap seat. The base comprises an air inlet passage and an air outlet passage in opposite directions. Each of the air inlet passage and the air outlet passage is provided with an air washer, a locating sleeve, a spring, and a block in sequence. The pressure in the tank and the atmosphere pressure produce a pressure differential to be balanced through the air inlet passage and the air outlet passage.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a gasoline tank cap structure, in particular to one able to balance the air pressure between the tank and the atmosphere for safety reason.

2. Description of the Prior Art

A conventional vehicle gasoline tank on the market is covered by a cap. The tank is sealed by the cap to prevent gasoline from spill. When pumping gasoline, the cap is unscrewed and the pump gun is inserted to start pumping gasoline into the tank.

Another conventional tank comprises a main body which is secured to the open end of the tank and a cap secured on the main body. The cap has an opening at the center thereof. A removable cover is pivotally connected to the main body with elastic elements to seal the open end of the tank. When pumping gasoline, the pump gun is inserted into the tank through the opening of the cap, which pushes the removable cover away so that gasoline may be pumped directly into the tank. This design uses the elastic elements to urge the removable cover securely to the tank, which may cause the pressure in the tank different from the atmosphere pressure and damage the engine operation or even cause explosion.

SUMMARY OF THE INVENTION

It is the primary objective of the present invention to provide a gasoline tank cap structure, which comprises an air inlet passage and an air outlet passage to balance the pressure within the gasoline tank.

It is another objective of the present invention to provide a gasoline tank cap structure, which prolongs the life span of an engine and minimizes malfunction rate.

According to the present invention, there is provided a gasoline tank cap structure comprising a base, said base comprising an air inlet passage and an air outlet passage in opposite directions, said air inlet passage having an air inlet hole in a smaller diameter at the top of said base, said air outlet passage having an air outlet hole in a smaller diameter at the bottom of said base, each of said air inlet passage and said air outlet passage being provided with an air washer, a locating sleeve, a spring, and a block in sequence, said locating sleeve having a hole for said air washer to seat therein, said spring having one end engaging with said air washer and another end engaging with said block, said block having a through hole, and said base further comprising channels interconnecting with said air inlet hole and said air outlet hole of said air inlet passage and said air outlet passage, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of the present invention;

FIG. 2 is a side cross-sectional view of the present invention;

FIG. 3 is a bottom view of a base of the present invention;

FIG. 4 is a side cross-sectional view of the present invention showing a removable cover in an operating status;

FIG. 5 is a side cross-sectional view of the present invention showing air flown into the tank; and

FIG. 6 is a side cross-sectional view of the present invention showing air flown away from the tank.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIG. 1, a preferred embodiment of the present invention comprises a base 1, a cap 2 and a cap seat 3.

The base 1 comprises a through hole 11, a first engaging section 12, and a second engaging section 13 at the top and the bottom of the base 1. The base 1 has an air inlet passage 14 at one end and an air outlet passage 15 at the opposite end of the air inlet passage 14. The air inlet passage 14 has an air inlet hole 141 in a smaller diameter at the top of the base 1, and the air outlet passage 15 has an air outlet hole 151 in a smaller diameter at the bottom of the base 1. The air inlet passage 14 is provided with an air washer 142, a locating sleeve 143, a spring 144, and a block 145 in sequence. The air outlet passage 15 is provided with an air washer 152, a locating sleeve 153, a spring 154, and a block 155 in sequence. The locating sleeve 143 has a hole 146 for the air washer 142 to seat therein. The locating sleeve 153 has a hole 156 for the air washer 152 to seat therein. One end of the spring 144 engages with the air washer 142 while the other end of the spring 144 engages with the block 145. One end of the spring 154 engages with the air washer 152 while the other end of the spring 154 engages with the block 155. The block 145 has a through hole 147. The block 155 has a through hole 157. As shown in FIGS. 1 and 3, the base 1 further comprises channels 16 and 17 interconnecting with the air inlet hole 141 and the air outlet hole 151 of the air inlet passage 14 and the air outlet passage 15, respectively.

The cap 2 comprises a third engaging section 21 at the bottom thereof to be engaged with the first engaging section 12 of the base 1. An opening 22 is formed in the center of the cap 2.

The cap seat 3 comprises a fourth engaging section 31 at the top thereof to be engaged with the second engaging section 12 of the base 1. A removable cover 32 is pivotally connected to the cap seat 3.

To pump gasoline into a tank incorporated with the present invention, as shown in FIG. 4, the pump gun is inserted into the tank through the opening 22 of the cap 2 and the through hole 11 of the base 1. The gun will push the removable cover 32 of the cap seat 3 away for the gun to be inserted direct into the tank. Should the atmosphere pressure is bigger then the pressure in the tank, as shown in FIG. 5, the tank will have a sucking force which moves the air washer 142 in the air inlet passage 14 away from the air inlet hole 141 to depress the spring 144, thus outside air is able to flow through the channel 16, the air inlet hole 141, the air inlet passage 14, the through hole 147 of the block 145, and the channel 17 in sequence into the tank. The air pressure between the tank and the atmosphere will reach a balanced situation.

When the pressure in the tank is bigger than the atmosphere, as shown in FIG. 6, the tank will have a push force which moves the air washer 152 in the air outlet passage 15 away from the air outlet hole 151 to depress the spring 154, thus the air in the tank may be flown through the channel 16, the air outlet passage 15, the through hole 157 of the block 155, and the channel 17 outward, balancing the pressure in and out of the tank. 

1. A gasoline tank cap structure comprising: a base comprising a through hole, a first engaging section and a second engaging section at the top and the bottom thereof; a cap comprising a third engaging section at the bottom thereof to be engaged with said first engaging section of said base, said cap further comprising an opening at the center thereof; a cap seat comprising a fourth engaging section at the top thereof to be engaged with said second engaging section of said base, a removable cover being pivotally connected to said cap seat; and characterized by: said base comprising an air inlet passage and an air outlet passage in opposite directions, said air inlet passage having an air inlet hole in a smaller diameter at the top of said base, said air outlet passage having an air outlet hole in a smaller diameter at the bottom of said base, each of said air inlet passage and said air outlet passage being provided with an air washer, a locating sleeve, a spring, and a block in sequence, said locating sleeve having a hole for said air washer to seat therein, said spring having one end engaging with said air washer and another end engaging with said block, said block having a through hole, and said base further comprising channels interconnecting with said air inlet hole and said air outlet hole of said air inlet passage and said air outlet passage, respectively. 